Clean burning bio-coal

ABSTRACT

A clean burning bio-coal consists of 70˜90 wt % of bio-fiber material and 1˜20 wt % of coal material. With the above composition percentages for the bio-fiber material and the coal material, emission of greenhouse gases and pollution gases during burning of the bio-coal can be reduced, total heat energy producible from the bio-coal is high enough to satisfy requirements in industrial activities, and a high burn-out rate of the bio-coal can be advantageously achieved.

FIELD OF THE INVENTION

The present invention relates to a bio-coal, and more particularly to a clean burning bio-coal that consists of bio-fiber material and coal material to achieve the purpose of environmental protection through recycling agricultural wastes and reducing the emission of greenhouse gases and pollution gases, and to produce total heat energy high enough to meet requirements in industrial activities.

BACKGROUND OF THE INVENTION

In environmental protection, recycling forms a basic spirit thereof. There is an environment-friendly charcoal, which uses agricultural wastes, such as straws, corn stalks, wood dust, and coconut shells as its major raw materials. By using the environment-friendly charcoal to replace the conventional coal material, it is able to avoid the emission of greenhouse gases and pollution gases, which are usually produced during burning of the conventional coal material, and to comply with the target of recycling in environmental protection. Taiwan Patent Publication No. 200533740 discloses a method for manufacturing artificial anthracite, so that recyclable agricultural wastes and plastic wastes can be further utilized. In the method of Taiwan Patent Publication No. 200533740, agricultural wastes are pulverized into smaller pieces, and the pulverized agricultural wastes are carbonized via processing under a high-temperature and oxygen-free environment, so as to form powdered carbon. The powdered carbon is then mixed with plastic wastes, and the mixture is fully stirred and blended before being positioned in a closed container having negative internal pressure. The mixture in the closed container is heated while being stirred. The raw material from the plastic wastes is molten in the heating process to thereby bind and shape the powdered carbon for use. While the environment-friendly charcoal so manufactured has high fuel value and meets the recycling requirements in environmental protection, the plastic wastes contained therein will produce waste gas with unpleasant odor when the environment-friendly charcoal is burning. Even if human-harmless plastic wastes are selected for use in the environment-friendly charcoal, it is still difficult for general consumers to accept it due to the bad odor.

Taiwan Patent Publication No. 200806782 discloses a method of manufacturing environment-friendly smokeless charcoal using agricultural wastes as the major raw material thereof. In the method, agricultural wastes are carbonized under a high temperature between 1500° C. and 1700° C., and botanical binder, such as glutinous rice dough, is mixed with the carbonized and pulverized agricultural wastes. The mixture is then extruded using an extruder to form a shaped product for use. The environment-friendly smokeless charcoal manufactured in the above method meets the recycling requirement in environmental protection and has the advantages of providing stable burning and not containing chemical substances.

It is known that various industrial activities largely rely on the coal material because the coal material supplies high amount of heat energy. However, the botanical fiber material provides only limited heat energy, and the currently available environment-friendly charcoal made from the botanical biomass in the agricultural wastes can not produce heat energy high enough to meet the amount needed by various industrial activities. While the adding of coal material to the botanical fiber material can increase the producible heat energy of the environment-friendly charcoal, the added coal material inevitably results in the emission of greenhouse gases and pollution gases.

Therefore, it is necessary to improve and more clearly define the composition percentages for the environment-friendly charcoal, so as to utilize the agricultural wastes as raw material of the environment-friendly charcoal to fully meet the principle of environmental protection and produce sufficient heat energy to satisfy the need in industrial activities without emitting greenhouse gases and pollution gases.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a clean burning bio-coal consisting of bio-fiber material and coal material at specific composition percentages, such that the alkaline bio-fiber material can neutralize the acidic coal material to thereby reduce the emission of greenhouse gases, such as carbon dioxide and sulfur dioxide, as well as other pollution gases, such as nitrogen oxide compounds.

Another object of the present invention is to provide a clean burning bio-coal that uses bio-fiber material as a main raw material thereof to achieve the purpose of recycling agricultural wastes, environmental protection, and energy saving, and uses coal material as a secondary raw material thereof to compensate the insufficient heat energy production ability of the bio-fiber material, so that the bio-coal can produce total heat energy high enough to meet requirements in industrial activities.

A further object of the present invention is to provide a bio-coal consisting of bio-fiber material and coal material that are fully blended with each other and uniformly distributed in the bio-coal, so that when the bio-coal burns, the bio-fiber material is burned out first to produce a burning porous briquette, which allows sufficient supply of oxygen into the bio-coal to enable complete combustion and accordingly increased burn-out rate.

To achieve the above and other objects, the clean burning bio-coal according to the present invention consists of 70˜90 wt % of bio-fiber material and 1˜20 wt % of coal material. With the above specific composition percentages of bio-fiber material and coal material, the bio-coal can produce total heat energy high enough to meet requirements in industrial activities. Furthermore, the alkaline calcium ions in the bio-fiber material fully react with acidic sulfur ions in the coal material to produce solid ashes, instead of reacting with oxygen atoms to produce sulfur dioxide, which reduces the emission of greenhouse gases and pollution gases during burning of the bio-coal. Also, when the bio-coal burns, the bio-fiber material thereof is burned out first to produce a burning porous briquette, allowing sufficient supply of oxygen into the bio-coal to enable complete combustion and accordingly increased burn-out rate of the bio-coal.

In a preferred embodiment of the present invention, the bio-fiber material is a carbon-containing botanical substance.

In an operable embodiment of the present invention, the carbon-containing botanical substance can be selected from the group consisting of different agricultural wastes, including wood dust, corn stalks, rice straws, wheat straws, cotton stalks, peanut vines, sweet potato vines, bark, palms, bagasses, and any combination thereof.

In another operable embodiment of the present invention, the coal material is selected from the group consisting of peat, brown coal, soft coal, hard coal, and any combination thereof.

The content of the coal material in the bio-coal of the present invention can be adjusted according to the type of the selected bio-fiber material, so that the bio-coal can produce total heat energy no less than 5000 Kcal per kilogram to meet the requirements in warming, cooking and other industrial activities, and the emission of carbon dioxide, sulfur dioxide, and nitrogen oxide compounds can be reduced. For example, when wood dust having relatively high heat energy is selected, the wt % of the coal material can be reduced; or when corn stalks having relatively low heat energy are selected, the wt % of the coal material can be increased.

However, the adjusted wt % for the bio-fiber material and the coal material should still fall in the composition percentage ranges set for them according to the present invention. That is, the bio-fiber material should account for 70˜90 wt % of the total weight of the bio-coal, and the coal material should account for 1˜20 wt % of the total weight of the bio-coal.

According to an ideal embodiment of the present invention, when the bio-fiber material and the coal material are subjected to a heating process, the bio-fiber material will release oil originally contained therein, and the released oil can serve as a natural binder to advantageously bind all material components together without the need of adding other binding agent.

In the case the naturally released oil is not sufficient for effectively shaping the bio-coal, according to an operable embodiment of the present invention, a botanical binder accounting for 1˜5 wt % of the total weight of the bio-coal can be added. The added botanical binder will become sticky after being heated, and can therefore help in fully binding all the components to shape the bio-coal. By using the botanical binder, it is able to avoid the drawback of producing too much ashes as in the case of conventional plastic binder.

According to an operable embodiment of the present invention, the botanical binder is starch.

In another operable embodiment of the present invention, a burning resistant accounting for 1˜10 wt % of the total weight of the bio-coal can be further added, so that the bio-coal can be more durable for burning.

According to an operable embodiment of the present invention, the burning resistant is clay.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments.

The present invention relates to a clean burning bio-coal, which consists of 70˜90 wt % of bio-fiber material and 1˜20 wt % of coal material. The following describes a manufacturing process of the clean burning bio-coal of the present invention.

The bio-fiber material is prepared by selecting one or more items from the group consisting of wood dust, corn stalks, rice straws, wheat straws, cotton stalks, peanut vines, sweet potato vines, bark, palms, and bagasses, all of which are carbon-containing botanical substances. The selected item or items are cut into relatively small raw material cubes using a dicer. The raw material cubes are then crushed using a crusher into fine pieces to complete the preparation of bio-fiber material. During the dicing and crushing processes, since water remaining in the raw material naturally dries, it is not necessary to consider the water content in the carbon-containing botanical substances being selected for use.

The coal material is prepared by selecting at least one item from the group consisting of peat, brown coal, soft coal and hard coal. The selected item or items are pulverized using a pulverizer. The wt % of the coal material in the bio-coal can be adjusted according to the selected bio-fiber material, so that a level of total heat energy production of at least 5000 Kcal per kilogram (Kcal/kg) can be achieved. For example, in the case the bio-fiber material is prepared using wood dust that can produce relatively high amount of heat energy, the wt % of the coal material can be properly reduced; or in the case the bio-fiber material is prepared using corn stalks that can only produce relatively low amount of heat energy, the wt % of the coal material can be properly increased. However, the adjusted wt % of the bio-fiber material and of the coal material must still fall in the composition percentages set for the clean burning bio-coal of the present invention. That is, the content of the bio-fiber material should be within the range from 70 to 90 wt % of the total weight of the bio-coal, and the content of the coal material should be within the range from 1 to 20 wt % of the total weight of the bio-coal.

Then, the properly proportioned bio-fiber material fine pieces and pulverized coal material are positioned in a mixer and fully blended to form a half-finished bio-coal having evenly distributed bio-fiber material and coal material. In an ideal embodiment of the present invention, it is not necessary to add any bonding agent to the bio-fiber material and the coal material in the mixing process.

In a first operable embodiment of the present invention, an amount of starch about 1˜5 wt % of the total weight of the bio-coal is further added to serve as a botanical binder and be uniformly blended into the bio-fiber material and the coal material by the mixer.

In a second operable embodiment of the present invention, an amount of clay about 1˜10 wt % of the total weight of the bio-coal is further added to serve as a burning resistant and be uniformly blended into the bio-fiber material and the coal material by the mixer.

The fully blended half-finished bio-coal is further processed using a plodder. The plodder includes a feed inlet, and is internally provided a pressing unit, a heating unit, and an extrusion-hole unit. The half-finished bio-coal is fed into the plodder via the feed inlet, and then pressed before being sent to the extrusion-hole unit. During the pressing process, the half-finished bio-coal is heated by the heating unit to a temperature of 150˜200° C., which is high enough to melt oil that is originally existed in the bio-fiber material. The molten oil flows out of the bio-fiber material to serve as a natural binder to advantageously bind all components in the raw material, so that the half-finished bio-coal is shaped. In the above-mentioned first operable embodiment of the present invention, the added starch is heated in the heating process and becomes sticky to serve as a natural binder to advantageously bind together all components in the raw materials. Thereafter, the half-finished bio-coal is extruded through the extrusion-hole unit preset on the plodder to form a configuration corresponding to the geometrical shape of the extrusion hole. At this point, the bio-coal of the present invention is formed.

The clean burning bio-coal of the present invention has the following features:

-   (1) The emission of carbon dioxide and sulfur dioxide from the     bio-coal of the present invention is less than 1%, which complies     with the related international standard; -   (2) The emission concentration of nitrogen oxide compounds from the     bio-coal of the present invention is not higher than 100 mg per     standard cubic meter; -   (3) The emission concentration of combustible dust from the bio-coal     of the present invention does not exceed 100 mg per standard cubic     meter; -   (4) The heat energy producible from the bio-coal of the present     invention is higher than 5000 Kcal per kilogram; and -   (5) The burn-out rate of the bio-coal of the present invention is as     high as 97.8%.

The emission of sulfur dioxide comes from the combustion reaction of sulfur in the coal material with oxygen in the air. However, due to the properly proportioned bio-fiber material and coal material for forming the bio-coal of the present invention, alkaline calcium ions in the bio-fiber material can fully react with acidic sulfur ions in the coal material to produce solid ashes, instead of reacting with oxygen atoms to produce sulfur dioxide.

Conventionally, high concentration of calcium ions in the bio-coal would frequently result in the drawback of reduced burn-out rate of the bio-coal. However, the bio-coal according to the present invention has fully blended and uniformly distributed components. Therefore, when the bio-coal of the present invention burns, the bio-fiber material therein will burn out first, and the positions originally occupied by the burned out bio-fiber material will form a plurality of pores, bringing the bio-coal to form a porous briquette. These pores allow sufficient supply of air into the bio-coal to enable extremely high heat transfer efficiency and accordingly, ensure complete burning of the coal material.

In conclusion, the present invention provides a clean burning bio-coal consisting of 70˜90 wt % of bio-fiber material and 1˜20 wt % of coal material. With the above composition percentages for the bio-fiber material and the coal material, the bio-coal of the present invention can produce total heat energy high enough to satisfy requirements in industrial activities. With the present invention, alkaline calcium ions in the bio-fiber material will fully react with acidic sulfur ions in the coal material to produce solid ashes, instead of reacting with oxygen atoms to produce sulfur dioxide. Therefore, the emission of greenhouse gases, such as carbon dioxide, sulfur dioxide, etc., as well as other pollution gases, such as nitrogen oxide compounds, all can be reduced. Meanwhile, when the bio-coal of the present invention burns, the bio-fiber material thereof will be burned out first to produce a burning porous briquette, which allows sufficient supply of air into the bio-coal to enable extremely high heat transfer efficiency and accordingly, ensure complete burning of the coal material.

The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. 

1. A clean burning bio-coal, comprising bio-fiber material and coal material, wherein the bio-fiber material accounts for 70˜90 wt % of a total weight of the bio-coal, and the coal material accounts for 1˜20 wt % of the total weight of the bio-coal to enable production of total heat energy high enough to satisfy requirements in industrial activities.
 2. The bio-coal as claimed in claim 1, wherein the bio-fiber material is a carbon-containing botanical substance.
 3. The bio-coal as claimed in claim 2, wherein the carbon-containing botanical substance is selected from the group consisting of different agricultural wastes, including wood dust, corn stalks, rice straws, wheat straws, cotton stalks, peanut vines, sweet potato vines, bark, palms, bagasses, and any combination thereof.
 4. The bio-coal as claimed in claim 1, wherein the coal material is selected from the group consisting of peat, brown coal, soft coal, hard coal, and any combination thereof.
 5. The bio-coal as claimed in claim 2, wherein the coal material is selected from the group consisting of peat, brown coal, soft coal, hard coal, and any combination thereof.
 6. The bio-coal as claimed in claim 4, further comprising a botanical binder added to the bio-fiber material and the coal material, and the added botanical binder accounting for 15 wt % of the total weight of the bio-coal.
 7. The bio-coal as claimed in claim 5, further comprising a botanical binder added to the bio-fiber material and the coal material, and the added botanical binder accounting for 15 wt % of the total weight of the bio-coal.
 8. The bio-coal as claimed in claim 6, wherein the botanical binder is starch.
 9. The bio-coal as claimed in claim 7, wherein the botanical binder is starch.
 10. The bio-coal as claimed in claim 4, further comprising a burning resistant added to the bio-fiber material and the coal material, and the added burning resistant accounting for 1˜10 wt % of the total weight of the bio-coal.
 11. The bio-coal as claimed in claim 5, further comprising a burning resistant added to the bio-fiber material and the coal material, and the added burning resistant accounting for 1˜10 wt % of the total weight of the bio-coal.
 12. The bio-coal as claimed in claim 10, wherein the burning resistant is clay.
 13. The bio-coal as claimed in claim 11, wherein the burning resistant is clay.
 14. A clean burning bio-coal, comprising bio-fiber material and coal material, wherein alkaline calcium ions in the bio-fiber material fully react with acidic sulfur ions in the coal material to produce solid ashes, instead of reacting with oxygen atoms to produce sulfur dioxide, so that emission of greenhouse gases and pollution gases during burning of the bio-coal is reduced.
 15. The bio-coal as claimed in claim 14, wherein the bio-fiber material accounts for 70˜90 wt % of a total weight of the bio-coal, and the coal material accounts for 1˜20 wt % of the total weight of the bio-coal.
 16. The bio-coal as claimed in claim 14, wherein the bio-fiber material is a carbon-containing botanical substance.
 17. The bio-coal as claimed in claim 15, wherein the bio-fiber material is a carbon-containing botanical substance.
 18. The bio-coal as claimed in claim 14, further comprising a botanical binder added to the bio-fiber material and the coal material, and the added botanical binder accounting for 1˜5 wt % of the total weight of the bio-coal.
 19. The bio-coal as claimed in claim 15, further comprising a botanical binder added to the bio-fiber material and the coal material, and the added botanical binder accounting for 1˜5 wt % of the total weight of the bio-coal.
 20. The bio-coal as claimed in claim 14, further comprising a burning resistant added to the bio-fiber material and the coal material, and the added burning resistant accounting for 1˜10 wt % of the total weight of the bio-coal.
 21. The bio-coal as claimed in claim 15, further comprising a burning resistant added to the bio-fiber material and the coal material, and the added burning resistant accounting for 1˜10 wt % of the total weight of the bio-coal.
 22. A clean burning bio-coal, comprising bio-fiber material and coal material that are fully blended with each other, whereby when the bio-coal burns, it is the bio-fiber material that burns out first to produce a burning porous briquette, which enables an increased burn-out rate of the bio-coal.
 23. The bio-coal as claimed in claim 22, wherein the bio-fiber material accounts for 70˜90 wt % of a total weight of the bio-coal, and the coal material accounts for 1˜20 wt % of the total weight of the bio-coal.
 24. The bio-coal as claimed in claim 22, wherein the bio-fiber material is a carbon-containing botanical substance.
 25. The bio-coal as claimed in claim 23, wherein the bio-fiber material is a carbon-containing botanical substance.
 26. The bio-coal as claimed in claim 22, further comprising a botanical binder added to the bio-fiber material and the coal material, and the added botanical binder accounting for 1˜5 wt % of the total weight of the bio-coal.
 27. The bio-coal as claimed in claim 23, further comprising a botanical binder added to the bio-fiber material and the coal material, and the added botanical binder accounting for 15 wt % of the total weight of the bio-coal.
 28. The bio-coal as claimed in claim 22, further comprising a burning resistant added to the bio-fiber material and the coal material, and the added burning resistant accounting for 1˜10 wt % of the total weight of the bio-coal.
 29. The bio-coal as claimed in claim 23, further comprising a burning resistant added to the bio-fiber material and the coal material, and the added burning resistant accounting for 1˜10 wt % of the total weight of the bio-coal. 